Prime Minister Shinzo Abe has expressed hope that revisions to the postwar Constitution will come into force in 2020 and that the existence of the Self-Defense Forces (SDF) will be clearly defined in the supreme law's war-renouncing Article 9.

Abe made the remarks on May 3 -- Constitution Day -- in a video message to a group promoting constitutional amendment. He also outlined constitutional provisions that he wants changed. By expressing his strong desire to revise the supreme law, he apparently encouraged the Diet and the Japanese people to hold proactive debate on the issue.

Opinions persist that the Constitution should clearly provide for the existence of the SDF. Junior ruling coalition partner Komeito is considering the matter as part of its policy of retaining the fundamental framework of the Constitution and adding more clauses to reinforce the supreme law's basic principles. Prime Minister Abe's proposal is significant to a certain extent, as both pro- and anti-amendment forces regard Article 9 as the core of the debate.

However, there are numerous problems with immediately launching discussions on Abe's proposals.

Firstly, the prime minister said he wants to see a new Constitution come into force in 2020, the year of the Tokyo Olympics and Paralympics. Constitutional amendments are completely irrelevant to the games. It appears as if the prime minister came up with the idea out of his desire to be re-elected to a third term as president of the ruling Liberal Democratic Party (LDP) in September 2018, and achieve constitutional revisions while in office.

That he makes light of the Diet should also be called into question. The House of Representatives Commission on the Constitution is discussing challenges involving relations between the national and local governments, among other issues, by inviting experts to panel sessions. The LDP, meanwhile, is prioritizing efforts to coordinate views with the largest opposition Democratic Party.

Commissions on the Constitution in both houses of the Diet are the only bodies that are authorized to deliberate revisions to the Constitution. Therefore, it is inappropriate to simply form a consensus on how the supreme law should be changed with those in favor of constitutional amendments, such as Komeito, while ignoring the commissions.

Prime Minister Abe has proposed adding a paragraph defining the existence of the SDF to Article 9 while retaining its first paragraph that renounces war, and the second paragraph banning Japan from possessing any war potential. It appears to be a departure from his earlier position to fundamentally revise paragraph 2 to provide for the establishment of a national defense military.

The government interprets Article 9 of the supreme law as permitting the SDF's existence. The SDF has engaged in disaster relief operations and participated in U.N. peacekeeping operations, and its activities have been widely accepted and highly appreciated by the general public.

Nevertheless, the prime minister insisted in his video message that Article 9 should be amended, citing some constitutional scholars' arguments that the SDF is unconstitutional. He is far from convincing.

Some experts are arguing that the SDF surpasses the minimum necessary capacity for self-defense and constitutes war potential banned under Article 9. It remains unclear how the definition of the SDF would be kept consistent with the war potential clause.

Abe's reference to "a new constitution" in his video message reflects his desire to create a "made-in-Japan" constitution to replace the current charter, which he feels strongly was forced on Japan by the United States following World War II.

Since Article 9 is the core of the Constitution that defines the basic principle of Japan, whether to amend it should be discussed with great care.